set trailer gross vehicle weight in engineering adapter

VectoCore/VectoCore/InputData/Reader/DataObjectAdapter/DeclarationDataAdapter.cs

@@ -94,7 +94,6 @@ namespace TUGraz.VectoCore.InputData.Reader.DataObjectAdaper
 			}
 
 			var retVal = SetCommonVehicleData(data);
-			retVal.GrossVehicleWeight = data.GrossVehicleMassRating;
 			retVal.TrailerGrossVehicleWeight = mission.TrailerGrossVehicleWeight;
 			retVal.CurbWeight += mission.BodyCurbWeight + mission.TrailerCurbWeight;
 			retVal.Loading = loading;

VectoCore/VectoCore/InputData/Reader/DataObjectAdapter/EngineeringDataAdapter.cs

@@ -57,6 +57,7 @@ namespace TUGraz.VectoCore.InputData.Reader.DataObjectAdaper
 			var retVal = SetCommonVehicleData(data);
 
 			retVal.CurbWeight += data.CurbWeightExtra;
+			retVal.TrailerGrossVehicleWeight = 0.SI<Kilogram>();
 			retVal.Loading = data.Loading;
 			retVal.DynamicTyreRadius = data.DynamicTyreRadius;
 			retVal.CrossWindCorrectionMode = data.CrossWindCorrectionMode;